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51.
Five 3'-fluorinated ribonucleosides were prepared and evaluated for their inhibitory properties against different viruses. The synthesis of these compounds was achieved by treatment of 2',5'-di-O-tritylated nucleoside analogues possessing a xylo-configuration with diethylaminosulfur trifluoride, followed by deprotection. 3'-Fluoro-3'-deoxyadenosine was active against a broad range of viruses, encompassing both DNA viruses [pox (vaccinia)], single-stranded (+) RNA viruses [picorna (polio, Coxsackie B), toga (sindbis, Semliki Forest)] and double-stranded RNA viruses (reo). In its antiviral activity spectrum 3'-fluoro-3'-deoxyadenosine clearly differed from those adenosine analogues that are known as inhibitors of S-adenosylhomocysteine hydrolase. 3'-Fluoro-3'-deoxyadenosine also proved effective in vivo, in inhibiting tail lesion formation in mice inoculated intravenously with vaccinia virus.  相似文献   
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A quantitative assay for ALZ-50 immunoreactivity was evaluated in samples of superior temporal gyrus taken at autopsy from 13 Alzheimer patients and 11 controls. The assayable immunoreactivity appears to be stable for at least 24 hours postmortem but was lost with formalin fixation. The mean value of the Alzheimer patients was tenfold higher than that of the controls (P less than .002). The values of four Alzheimer samples overlapped with the low levels seen in controls, but no controls had elevated levels. In this sample population, therefore, the assay had a sensitivity of 69% and specificity of 100%.  相似文献   
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The absolute activities of the pure beta-emitters 89Sr and 90Y have been determined by a direct method, namely the triple-to-double coincidence ratio (TDCR) efficiency calculation technique. This undertaking has extended further the number of radionuclides that have been standardized by this non-extrapolation liquid scintillation (LS) method. Both measurements were carried out within the framework of international key comparisons under the auspices of the International Bureau of Weights and Measures (BIPM). The TDCR results agreed well with those of other participating national laboratories, most using alternative (tracer) methods.  相似文献   
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Objective. We studied long‐term clinical efficacy of sacral neuromodulation (SNM) therapy in patients with refractory urgency incontinence (UI), urgency/frequency (UF) and voiding difficulty (VD), together with urodynamic data at baseline and six   months postimplant. Materials and Methods. Twenty‐two patients were implanted with a neurostimulator after a positive response to a percutaneous nerve evaluation test defined as a greater than 50% improvement in symptoms. Results. At five‐year follow‐up, the number of incontinent episodes and pad usage per day decreased significantly in 10 out of 15 UI patients. Two of five UF patients were successfully treated with SNM; the number of daily voids for all UF patients decreased from 25 to 19 and average voided volume increased from 98 to 212 mL. One of the two VD patients was able to void to completion. Mean first sensation of filling at the six‐month urodynamic investigation for the UI and UF patients increased from 78 to 241 mL and 141 to 232 mL, respectively, and the maximum bladder capacity increased from 292 to 352 mL and 223 to 318 mL, respectively. Five of 22 patients underwent device explant and one patient still has an inactive stimulator implanted. Conclusion. SNM is an effective treatment modality that offers sustained clinical benefit in the majority of patients with refractory UI, UF, and VD that do not respond to other, more conservative therapies.  相似文献   
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International Journal of Clinical Pharmacy - In order to calculate the minimum sterilization process conditions to obtain the generally accepted sterility level (less than 1·10?6...  相似文献   
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The effects of intracerebral implants of 17 beta estradiol and cholesterol in five brain regions were tested on the duration of the dorsal immobility response in ovariectomized female rats. The dorsal immobility response was significantly prolonged by 4-hr implants of 17 beta estradiol in the dorsal striatum and nucleus accumbens, but not in the cortex, the globus pallidus, or the substantia nigra pars compacta. These data further support previous evidence that estradiol acts directly on the striatum to affect behavior in the rat.  相似文献   
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Mycobacterium ulcerans infection in Ashanti region, Ghana   总被引:1,自引:0,他引:1  
We describe a series of 96 cases of Mycobacterium ulcerans infection (Buruli ulcer) from a new endemic focus in the Afram valley, north of Agogo, in Ghana. 63 cases were children under 13 years old. Active treatment by excision and skin grafting necessitates long stays in hospital and repeated procedures. Scarring and contracture are frequent. Eyes and other vital organs may be destroyed. In its endemic foci Buruli ulcer is a serious health burden on rural populations. Research is urgently needed, especially in prevention and non-surgical management.  相似文献   
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